ELECTRON MICROSCOPY OF <i>TREPONEMA PALLIDUM</i> NICHOLS

Jepsen, Otto; Hougen, K. Hovind; Bikch-Andersen, Aksel

doi:10.1111/j.1699-0463.1968.tb03477.x

Cited by 48 publications

(12 citation statements)

References 23 publications

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“…As seen in Fig. 1A and throughout, the bacteria retained their characteristic wave-like morphology (58,64,82). Side views of tomograms (Fig.…”

Section: Resultsmentioning

confidence: 76%

“…Following inoculation, usually in the genital region, T. pallidum disseminates via lymphatics and blood to diverse organs, where it can establish persistent, even life-long, infection (68,97). Over the years there has been great interest in defining ultrastructural features of the syphilis spirochete that might contribute to syphilis pathogenesis (58,64,84,120,121). Classic electron microscopy studies established that T. pallidum possesses a characteristic spirochete ultrastructure consisting of outer and cytoplasmic membranes and periplasmic flagellar filaments originating from cytoplasmic membrane-associated, subterminal basal bodies (55, 58).…”

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confidence: 99%

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Cryo-Electron Tomography Elucidates the Molecular Architecture ofTreponema pallidum, the Syphilis Spirochete

et al. 2009

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Cryo-electron tomography (CET) was used to examine the native cellular organization of Treponema pallidum, the syphilis spirochete. T. pallidum cells appeared to form flat waves, did not contain an outer coat and, except for bulges over the basal bodies and widening in the vicinity of flagellar filaments, displayed a uniform periplasmic space. Although the outer membrane (OM) generally was smooth in contour, OM extrusions and blebs frequently were observed, highlighting the structure's fluidity and lack of attachment to underlying periplasmic constituents. Cytoplasmic filaments converged from their attachment points opposite the basal bodies to form arrays that ran roughly parallel to the flagellar filaments along the inner surface of the cytoplasmic membrane (CM). Motile treponemes stably attached to rabbit epithelial cells predominantly via their tips. CET revealed that T. pallidum cell ends have a complex morphology and assume at least four distinct morphotypes. Images of dividing treponemes and organisms shedding cell envelope-derived blebs provided evidence for the spirochete's complex membrane biology. In the regions without flagellar filaments, peptidoglycan (PG) was visualized as a thin layer that divided the periplasmic space into zones of higher and lower electron densities adjacent to the CM and OM, respectively. Flagellar filaments were observed overlying the PG layer, while image modeling placed the PG-basal body contact site in the vicinity of the stator-P-collar junction. Bioinformatics and homology modeling indicated that the MotB proteins of T. pallidum, Treponema denticola, and Borrelia burgdorferi have membrane topologies and PG binding sites highly similar to those of their well-characterized Escherichia coli and Helicobacter pylori orthologs. Collectively, our results help to clarify fundamental differences in cell envelope ultrastructure between spirochetes and gram-negative bacteria. They also confirm that PG stabilizes the flagellar motor and enable us to propose that in most spirochetes motility results from rotation of the flagellar filaments against the PG.Spirochetes are an ancient and extremely successful eubacterial phylum characterized by distinctive helical or planar wave-form morphology and flagellar filaments confined to the periplasmic space (55, 87). Spirochetes from the genera Leptospira, Treponema, and Borrelia are highly invasive pathogens that pose public health problems of global dimensions (1,6,57,109). Treponema denticola and numerous other treponemal species, most of which remain uncultivated, are major components of the polymicrobial biofilms that cause periodontal disease (34, 56) and also have been implicated as risk factors for atherosclerosis (4,125). The treponemal symbionts that dwell in the hindguts of termites, where they provide their insect host with essential nutrients (10), are one of the most striking examples of the extraordinary biodiversity achieved by spirochetes. It is readily apparent, therefore, that in the course of their complex evolution, spiroc...

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“…As seen in Fig. 1A and throughout, the bacteria retained their characteristic wave-like morphology (58,64,82). Side views of tomograms (Fig.…”

Section: Resultsmentioning

confidence: 76%

mentioning

confidence: 99%

Cryo-Electron Tomography Elucidates the Molecular Architecture ofTreponema pallidum, the Syphilis Spirochete

et al. 2009

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“…11,6 In functional studies phagocytosis of opsonized T. pallidum by macrophages, 9,10 activated by IFN-␥, 10 has been demonstrated, and degraded T. pallidum organisms were found in phagocytic vacuoles of macrophages. 23,5 These observations combined with the fact that treponemas are extracellular bacteria gave reason to speculate that macrophages, activated by IFN-␥-pro- ϩ T-cells were the most likely candidates in rabbit models of syphilis infection, 19 other studies indicated a possible role for CD8 ϩ T-cells in providing this macrophage-activating cytokine. 7 The cellular course of events described in animals and also observed in humans infected with T. pallidum is similar to what we observed in our HIV Ϫ syphilitic patients.…”

Section: Discussionmentioning

confidence: 99%

Host Defense Mechanisms in Secondary Syphilitic Lesions

Stary

Klein

Brüggen

et al. 2010

The American Journal of Pathology

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Cell-mediated immunity is thought to be of critical importance in antisyphilitic host defense, but the exact mechanisms are still unknown. This fact is particularly true for HIV-infected persons with a deficit in CD4 ؉ T-cell number. We therefore obtained lesional skin samples from HIV ؉ and HIV ؊ patients with secondary syphilis at different time points of lesional age to search both for causative microorganisms and to characterize the inflammatory infiltrate. By doing so, we detected Treponema pallidum spirochetes with a much greater abundance in late lesions of HIV

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“…The periplasmic space contains endoflagella that facilitate the characteristic motility. 24 The genome of T. pallidum is much smaller (1.14 MDa) than that of, for example, Escherichia coli (4.6 MDa) and the bacterium has surprisingly little metabolic capability. It lacks tricarboxylic acid cycle enzymes and an electron transport chain.…”

Section: Syphilis Outlinementioning

confidence: 99%